What Is Partially Hydrolyzed Guar Gum?
Guar gum is typically used in small amounts as a food additive because it acts as a stabilizer, thickener, and binder. For example, guar gum can be added to cakes so that it is less crumbly when sliced or processed meats to help stabilize fat during storage.
Guar gum works well as a thickener and binder because of its high viscosity and water binding capabilities. These 2 functional properties make it a great food additive but also make it challenging to incorporate into food products in the amount necessary to use as dietary fiber. This is where the ‘partially hydrolyzed’ part comes into play.
Partially hydrolyzed guar gum
To be able to use guar gum as a dietary fiber, it has to go through a process called enzymatic hydrolysis. This involves breaking down guar gum’s carbohydrate structure into smaller carbohydrate chains.
The breakdown or ‘partial hydrolysis’ of guar gum not only changes its physical structure but also changes its’ functional properties.
So, where guar gum was highly viscous and water-binding, ‘partially hydrolyzed’ guar gum is now non-viscous and non-water binding. This makes it easy to eat in the necessary amounts to see its proposed health benefits like lowering blood sugar or cholesterol or, as we’ll talk about next, improving gut health.341
Does PHGG Help IBS?
The American College of Gastroenterology (ACG) recommends using soluble fiber to relieve ‘global’ IBS symptoms. 5But not all soluble fibers have the same functional properties. Meaning they can act differently in the digestive tract.
So, where does PHGG fall into all this?
PHGG is a soluble fiber, and along with being non-viscous, it is also slowly fermenting. But does it actually help relieve IBS symptoms? Let’s check out the research.
We came across just under 10 studies examining how PHGG affects IBS symptoms. And while we’ll admit that most of the studies weren’t exactly well designed, they all indicated some symptom relief for IBS in one way or another. We’ll touch on some of the study findings below.
Studies on PHGG for IBS
- For starters, the only randomized, double-blinded placebo-controlled study found that 6 g of PHGG helped improve bloating and gas in IBS patients compared to the placebo group. However, it did not improve stool frequency or abdominal pain.6
- One of the larger studies on PHGG looked at 188 IBS patients and showed that 5 g of PHGG improved pain and bowel habits and was better tolerated than 30 g of wheat bran.7
- Another study gave participants either 5 g or 10 g of PHGG per day; both groups showed an improvement in IBS symptoms, indicating that 5 g of PHGG may be the minimum dose needed to help aid in IBS symptom relief.8
- A few studies looked into how PHGG affects IBS-C patients, specifically.
- For example, a small study showed that 5 g of PHGG decreased abdominal bloating in men, decreased laxative use in women, and decreased stool transit time in both genders with IBS-C.9
- These results were replicated in another study on IBS-C patients by the same author; however, dosing information was not specified for the second study.10
Studies on PHGG for constipation
Outside of IBS, PHGG has shown to be helpful with aiding in constipation relief by different measurements like increasing the frequency of bowel movements or decreasing the use of laxatives.
A meta-analysis showed that 5-7g of PHGG was what was needed to increase bowel movement frequency. 11It seems PHGG can be pretty helpful in relieving constipation in non-IBS patients, but unfortunately, we can’t really predict how it may change bowel habits in IBS-C patients, and placebo-controlled studies are needed.
PHGG may also help via microbiome & SIBO
- More ways PHGG may be of interest to someone with IBS is how it may affect the microbiome. Some studies have shown that PHGG may increase Lactobacilli and Bifidobacteria–two types of gut bacteria associated with a healthy gut. 12One particular study showed that when patients with diarrhea were given 5 g of PHGG, they had increased Bifidobacteria along with some significant beneficial stool changes compared to the placebo group13.
- A recent study showed that PHGG aids in the eradication of small intestinal bacterial overgrowth (SIBO) when coupled with an antibiotic. 14There seems to be considerable overlap between SIBO and IBS, so this study demonstrated a new way that PHGG may help those with IBS; however, more research is needed to support the use of PHGG for this purpose.
The takeaway from these studies
While studies on PHGG in IBS patients have measured different outcomes and shown that it provides some sort of relief for IBS in general, it seems especially helpful for people with IBS who have gas, bloating, and possibly constipation.
PHGG could also be a safe way to add fiber to the diet, especially for someone avoiding FODMAPs, as it is considered FODMAP-friendly.15
How To Take PHGG For IBS
How much to take (dosing)
Clinical trials typically use 5g/day for dosing, so that may be a good goal to work up to if you decide to try PHGG.
Of course, before starting a new supplement, talk to your doctor. And whenever increasing fiber in the diet, we suggest a slow and steady approach in addition to extra water.